Option to specify the path for the sly.json file

[ndozhh]

Hi Jacob, thank you for your work in this package, it works great.

I was trying to setup it in a monorepo inside packages/icons, using Turborepo. The problem is that the dependency is always installed in the root node_modules and not in packages/icons/node_modules, so when I try to use a transformer I got this error:

Failed to load transformer transform-icon.ts.
Sly must be installed to your node_modules to use typescript transformers.
npm install --save-dev @sly-cli/sly

I can use the option --cwd to tell it where to pick up the dependency but now the sly.json and the transform-icon.ts files should be placed at the root of the monorepo, but I want them to be inside my packages/icons package.

Based on this context, I think it would be very useful if we can specify an option with the path for the sly.json file.